1. Field of the Invention
The present invention relates to a pushbutton switch comprising a pushbutton for changing a switching mode of a tact switch provided on a switch holder fixedly disposed within a casing, the pushbutton including a push operation portion disposed in a through hole provided in the casing and a collar that protrudes outwardly from the push operation portion and faces an inner face of the casing at a peripheral edge of the through hole, the pushbutton being provided so as to be connected to the switch holder and being resiliently urged toward the side on which the collar gets closer to the inner face of the casing.
2. Description of the Related Art
Such a pushbutton switch is already known, as disclosed in Japanese Patent No. 3944975, and the like.
However, in the arrangement disclosed in Japanese Patent No. 3944975, in a non-operated state in which a pushbutton is not pushed into, the whole face of a collar of the pushbutton is in intimate contact with an inner face of a casing at the peripheral edge of a through hole. Because of this, in an environment in which an outer face of the casing is exposed to rainwater, etc. or in an environment in which humidity is high, moisture that has collected between the casing and the pushbutton freezes in response to a decrease in ambient temperature, and there is a possibility of a problem in the operation of the pushbutton being caused.